Introduction

rc1

There have been regressions since 2.6.39.

The kernel hangs waiting for the sd/mmc card.

Enabling USB results in very ugly kernel oops.

Something is amuck with the wl21xx support.

rc2

Looks like Tony Lindgren's pull request to Linus missed the release of -rc2 by a couple of hours, so no fixes got into -rc2.
We will have to wait a week or so for -rc3, an expanded mmc fix for the issue is included.

rc3

Well, -rc3 is out and the mmc issue is fixed, but the revert of commit 7e6502d577106fb5b202bbaac64c5f1b065e6daa is still necessary to let the kernel boot with ehci enabled, however something else has broken as the USB ethernet is not functional and DVI doesn't work either. It is of interest to note that there have been massive changes to wl12xx to support ap functionality, as well as massive changes in drivers/video/omap2/dss/.
So it seems that -rc3 is a further regression from 2.6.39.

rc4

-rc4 has fixed many of the issues introduced in rc3, however no progress with the issues introduced in 3.0.

The reversion of commit 7e6502d577106fb5b202bbaac64c5f1b065e6daa is still necessary.

The I2C patch is still necessary.

The DVI patch is still necessary.

The wl21xx still has problems, no temp fix available (yet).

rc5

-rc5 has quite a few changes to omap4 code, but no additional fixes from -rc4

The reversion of commit 7e6502d577106fb5b202bbaac64c5f1b065e6daa is still necessary.

The I2C patch is still necessary.

The DVI patch is still necessary.

The wl21xx still has problems, no temp fix available (yet).

rc6

A few OMAP and PandaBoard related changes in this update, none of the work form linux-omap-2.6.git has made it into mainline yet.

rc7

A bunch of OMAP related changes made it into this update, and with EHCI enabled, the kernel boots!
The kernel recognises a usb keyboard, mouse and various other devices as well as it's own usb-ethernet.
The DVI output works (at better resolution if you apply the DVI patch).
The i2c works with the i2c patch.
This is certainly an improvement over -rc6.
The WLAN is still broken.

more to come...... Look for an update to building x-loader & u-boot for PandaBoard in a few days (I hope, maybe I'll wait till 3.0 is released).

Or use the patch from this post: http://www.spinics.net/lists/linux-omap/msg52058.html
This will be required until the hwmod code is fixed. There is quite a bit of hwmod work going on in linux-omap-2.6.git so help may be on the way, but as of 6/29/2011 none of this work has made it into master of linux-omap-2.6.git. As of 7/11/2011 it seems that sufficient hwmod changes have been incorporated to
to make the revert unnecessary.

the following messages are still present during bootup (from -rc1 to -rc7):

The mmc patch is required for -rc1/2, as are the dvi patch (if you want anything other than 640x480) and the i2c patch.

Building

Building 3.0-rc1, -rc2, -rc4, -rc5, or -rc7 is basically the same as How to build 2.6.38 kernel, but of course you need the -rc1/2/4/5/7 sources. The omap2plus_defconfig works once the mmc patch is applied (for -rc1 & -rc2). config.3.0-rc2.1 works for the reverted commit, mmc patch, dvi patch and i2c patch. For -rc5 with patched sources use config.3.0-rc5.1. For -rc7 use config.3.0-rc7.1 (with DVI & i2c patch).

MMC Patch

A patch is available which addresses the mmc issue noted above, it is no longer required for -rc3, -rc4, -rc5, or -rc7:

The mmc issue has been fixed in linux-omap-2.6.git, as well as -rc3, -rc4, -rc5 and -rc7 but the oopses are still present when EHCI is enabled in .config, unless the above commit is reverted. -->>> no longer necessary for -rc7.

There is also an issue with the setting up of the wl12xx in -rc1/2/4/5/7:

[ 0.181457] error setting wl12xx data

Which is a problem new to 3.0-rc1/2, still present in -rc3, -rc4, -rc5 and -rc7 as well as linux-omap-2.6.git. Although the error is not present in the reverted -rc2/4/5 & linux-omap-2.6.git, or in -rc7, the wlan does not appear to work.

DVI Patch

This patch is no longer strictly necessary, but without it the dvi output is 640x480. Applying it doesn't seem to hurt though.

Apply it like so: (from inside the kernel sources directory)

patch -p1 < 0001-omap4-pandaboard-fix-dvi-support.patch

Then use either of the following configs

make ARCH=arm omap2plus_defconfig
or
make ARCH=arm panda_dvi_defconfig

Then compile with

make ARCH=arm CROSS_COMPILE=Path_to_your/arm-2009q3/bin/arm-none-linux-gnueabi- uImage
or
make ARCH=arm CROSS_COMPILE=Path_to_your/arm-2010q1/bin/arm-none-linux-gnueabi- uImage